.shareMask{
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(0, 0, 0, 0.6);
    z-index: 1000;
    background-size: 80% auto;
    background-repeat: no-repeat;
    background-position: top center;
}
